Facile surfactant-free synthesis and luminescent properties of hierarchical europium-doped lutetium oxide phosphors.

Novel three-dimensional (3D) hierarchical architectures of Lu(2)O(3):Eu(3+) have been successfully prepared through a simple hydrothermal process followed by a subsequent calcination process without using any surfactant, catalyst, or template. According to the X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry, and Fourier transform infrared spectroscopy results, the precursors were determined to have the structure formula of Lu(4)O(OH)(9)NO(3). The morphologies of the precursors could be modulated by altering pH value of the reaction system. On the basis of detailed time-dependent experiments, the growth process of architectures was discussed. The as-formed precursors could transform into Lu(2)O(3):Eu(3+) with their original hierarchical structures maintained. The Lu(2)O(3):Eu(3+) submicro-architectures exhibit strong red emission corresponding to the (5)D(0)→(7)F(2) transition of the Eu(3+) ions under ultraviolet (UV) excitation, which have potential applications in novel optoelectronic devices.